SALT LAKE CITY — Wildfire smoke is blanketing Utah and the West, leading to ash falling on Portland, obscured mountain views along the Wasatch Front and unhealthy air as far east as Dubuque, Iowa.

More than 2,200 square miles is burning in nine Western states, according to the National Interagency Fire Center, with Oregon and Idaho each playing unwelcome host to 19 fires of more than 1,000 acres.

In Montana, close to a million acres have burned, while closer to home in Weber County, firefighters continue to battle a fast-moving mountainous blaze that destroyed five homes and another structure and prompted the evacuation of hundreds of people.

All this smoke is leading to unhealthy air.

"We are under this circulating high-pressure system that is bringing in smoke mostly from the north and west of us," said Bryce Bird, director of the Utah Division of Air Quality.

Pollution levels along most of the Wasatch Front, in Cache Valley and Carbon and Duchesne counties were classified as moderate early Wednesday afternoon. Measurements for ozone in Salt Lake County were at 65 parts per million (the standard is 70 parts per million, according to the U.S. Environmental Protection Agency) and ranged in the high 50s or 60s in many Wasatch Front counties.

Moderate conditions for air quality mean people from sensitive populations, including those with respiratory conditions and young children and the elderly, should avoid outdoor activity if possible. Additionally, the air quality division advises motorists to voluntarily refrain from driving as much as possible by telecommuting, carpooling or trip chaining.

The eerie pall settling over much of Utah from wildfire smoke makes conditions look horrible — and while not ideal — it could be much, much worse, Bryce said.

Ogden, for example, measured at 94, or moderate, Wednesday afternoon on the EPA's air quality index, which is a measurement of five major air pollutants regulated under the Clean Air Act. Provo hit a value of 126, while Salt Lake City sat at 115.

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Elsewhere, Spokane was teeming with pollutants at 244 for PM2.5, and Flathead Valley, Mont., was 216. In Oregon, Pendleton logged 238 on the index.

Wildfire smoke forced high school football teams to adjust their schedules in Medford, Oregon, and postpone marathons.

NASA reports, too, that other parts of the country are not immune from the effects of wildfires burning in the West.

The collective enormity of the blazes is sending smoke and particles high enough to be carried along the jet stream, traveling some 3,000 miles to the East Coast.

When the jet stream moved over Dubuque, Iowa, air pollution grew to an unhealthy level.

Twin studies from the Georgia Institute of Technology released earlier this summer revealed startling information about the impact of wildfires, including their impacts on health and their atmospheric reach.

One study found that pollution resulting from wildfires is three times greater than previous EPA estimates. Another study found that particles from wildfires reached as high as 7 miles into the atmosphere, showing up as "brown carbon," to potentially affect the climate.

In the emissions inventory looking at the amount of pollution generated by wildfires, researchers found an abundance of chemicals typically associated with industrial activity — methanol, benzene and other noxious chemicals posing hazards to human health.

NASA aircraft collected air samples from the upper troposphere — 7 miles above the Earth — finding levels of brown carbon or matter derived from burning trees and other organic matter.

The smoky skies are likely to stick around into Friday, when a changing weather pattern will bring a 30 percent chance of rain, according to forecasters.

Bird is hopeful the shifting weather pattern will be enough that it brings people some relief from one of the West's most-active wildlife seasons.

In the interim, Utah air quality regulators continue to battle pollution on another front — trying to craft a control plan that will bring fine particulate pollution, or PM2.5, to below EPA's federal threshold.

The Wasatch Front is under a "serious" nonattainment classification for violating federal Clean Air standards.

A pollution control plan is due by the end of this year, but one that will produce the desired result — coming into compliance — will miss that deadline.

"The real challenge is that we have not found any new and innovative approaches to reducing air pollution that we have not already put into place. We are working with stakeholders to determine what can be done," he said.

Members of the Utah Air Quality Board heard an update on the division's efforts on Wednesday.

Regulators have already required a number of new pollution-cutting controls for a variety of industries, businesses and consumers. Refineries installed $250 million worth of new technology related to emissions, and about a dozen rules were revamped targeting emissions from the application of paint and solvents.

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Even emissions from the use of hair spray and those that come from hot water heaters were covered in new pollution-busting rules.

Bird said the EPA is aware the 2017 deadline will come and go for the new plan, and there's a six-month window in which the federal agency has to act to acknowledge the delay or pursue some other action.

In some respects, the state agency has its back against the wall because it has been unable to come up with a plan that demonstrates it can bring pollution levels down below the threshold, he acknowledged.

"We've found dozens of new things that add up, but nothing that really moves the needle."

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